Dr. Rajnish Kumar’s research focuses on sustainable energy technologies, carbon management, and advanced water purification methods. His work bridges fundamental science with impactful applications, particularly in the areas of gas hydrates, carbon dioxide capture and sequestration, and clean energy storage materials.

Dr. Kumar's group has made groundbreaking advancements in the field of gas hydrates, studying their formation, inhibition, and potential for methane recovery from marine sources. His work on hydrate-based methane recovery has led to innovative approaches to capture methane sustainably and to manage flow assurance in pipelines. By exploring the role of specific additives in hydrate formation and inhibition, his team has developed methods to control hydrate behavior, contributing to safer and more efficient energy extraction processes.

In the area of carbon dioxide capture and sequestration (CCS), his group has developed novel materials and processes to capture CO₂, helping to mitigate greenhouse gas emissions. His work integrates CCS with gas hydrate technology, offering unique pathways for sustainable carbon management.

Dr. Kumar’s research also advances methane and hydrogen storage by designing and testing new materials that enable safe, efficient, and scalable storage solutions for clean energy applications. His focus on hydrate-based storage materials aims to facilitate the use of methane and hydrogen as alternative fuels in a sustainable energy landscape.

For water purification, Dr. Kumar’s team has developed a hydrate-based approach to remove contaminants and desalinate water. This innovative technology uses gas hydrate processes to capture impurities from water, providing an environmentally friendly and energy-efficient solution for clean drinking water. His group's technology has the potential to address drinking water challenges globally, especially in regions facing contamination and water scarcity.

Additionally, Dr. Kumar’s research in hydrothermal liquefaction explores biofuel production through the conversion of biomass at sub-critical and super-critical conditions. His group has developed methods to optimize these conditions, creating efficient biofuel production pathways that contribute to a sustainable energy future.

Through his research, Dr. Kumar has published over 120+ articles, delivered invited talks, and developed several patents. His pioneering work in gas hydrate-based technologies, CCS, and advanced material design is helping to solve some of the most critical challenges in clean energy and environmental engineering.